blundered up on (verb) stumble: happen upon
Sinonime: arrow,
axis, axle,
bar, barb,
beam, chimney, column,
conduit, cylinder, diaphysis, duct, flue,
handle, helve, hole, lance, missile, monolith, obelisk,
pillar,
pinnacle, pole, ray, rod, spear, spindle, spire, thill,
tongue, tunnel, vent
Antonime: lose,
overlook